Sodium → 2-(6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-4-yl)-4-methoxypyridine N-oxide

HRID 892544Notes

Reaction equation

HRID 892544 reaction equation
Cl[C:2]1[CH:7]=[CH:6][N+:5]([O-:8])=[C:4]([CH:9]2[C:14]3[CH:15]=[C:16]([C:19]#[N:20])[CH:17]=[CH:18][C:13]=3[O:12][C:11]([CH3:22])([CH3:21])[CH2:10]2)[CH:3]=1.[CH3:23][O-:24].[Na+].[Na]>CO>[C:19]([C:16]1[CH:17]=[CH:18][C:13]2[O:12][C:11]([CH3:22])([CH3:21])[CH2:10][CH:9]([C:4]3[CH:3]=[C:2]([O:24][CH3:23])[CH:7]=[CH:6][N+:5]=3[O-:8])[C:14]=2[CH:15]=1)#[N:20]

Participants

5

Reactant 3

HCID 5360545SodiumHCID 10942334Sodium MethoxideHCID 536365624-chloro-2-(6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-4-yl)pyridine N-oxide

Product 1

HCID 540288412-(6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-4-yl)-4-methoxypyridine N-oxide

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

250 mg of 4-chloro-2-(6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-4-yl)pyridine N-oxide were dissolved in 6 ml of methanol and added to a solution of sodium methoxide prepared from 0.5 g of metallic sodium in 50 ml of methanol. The mixture was heated at reflux for 2 hours under a nitrogen atmosphere and then allowed to cool to room temperature. The solution was evaporated and the residue was taken up in ethyl acetate and water, the organic phase was separated, dried over sodium sulphate and evaporated. The residue was chromatographed on silica gel using 20% (v/v) methanol/ethyl acetate for the elution to give a solid which was recrystallized from ethyl acetate. There were obtained 65 mg of 2-(6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-4 -yl)-4-methoxypyridine N-oxide of melting point 196°-198° C.

Workup

  1. temperatureThe mixture was heated
  2. temperatureat reflux for 2 hours under a nitrogen atmosphere
  3. customThe solution was evaporated
  4. customwater, the organic phase was separated
  5. dry with materialdried over sodium sulphate
  6. customevaporated
  7. customThe residue was chromatographed on silica gel using 20% (v/v) methanol/ethyl acetate for the elution
  8. customto give a solid which
  9. customwas recrystallized from ethyl acetate

Sources & evidence

ORD record
ord-e2888f727a64494e8ac7d54d0249ec8f
Source dataset
uspto-grants-1992_06
Patent number
US05118694

Reaction notes

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